The rising incidence of
cholangiocarcinoma (CCA) coupled with a low 5-year survival rate that remains below 10% delineates the urgent need for more effective treatment strategies. Although several recent studies provided detailed information on the genetic landscape of this fatal
malignancy, versatile model systems to functionally dissect the immediate clinical relevance of the identified genetic alterations are still missing. To enhance our understanding of CCA pathophysiology and facilitate rapid functional annotation of putative CCA driver and
tumor maintenance genes, we developed a tractable murine CCA model by combining the cyclization recombination (Cre)-lox system, RNA interference, and clustered regularly interspaced short palindromic repeats/
CRISPR associated protein 9 (CRISPR/Cas9) technology with liver organoids, followed by subsequent
transplantation into immunocompetent, syngeneic mice. Histologically, resulting
tumors displayed
cytokeratin 19-positive ductal structures surrounded by a desmoplastic stroma-hallmark features of human CCAs. Despite their initial biliary phenotype in vitro, organoids retained the plasticity to induce a broader differentiation spectrum of primary
liver cancers following
transplantation into recipient mice, depending on their genetic context. Thus, the organoid system combines the advantage of using nontransformed, premalignant cells to recapitulate liver
tumorigenesis as a multistep process, with the advantage of a reproducible and expandable cell culture system that abrogates the need for recurrent isolations of primary cells. Conclusion: Genetically modified liver organoids are able to transform into histologically accurate CCAs. Depending on the oncogenic context, they are also able to give rise to
liver cancers that show features of
hepatocellular carcinomas. The model can be used to functionally explore candidate cancer genes of primary
liver cancers in immunocompetent animals and evaluate novel treatment regimens.